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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Posted on 7 November 2011 by John Hartz

The following article, written by Jeremy Hance, was originally posted on Mongabay.com (Oct 24, 2011). It is reprinted here with permission.

If governments are to keep the pledge they made in Copenhagen to limit global warming within the 'safe range' of two degrees Celsius, they are running out of time, according to two sobering papers from Nature. One of the studies finds that if the world is to have a 66 percent chance of staying below a rise of two degrees Celsius, greenhouse gas emissions would need to peak in less than a decade and fall quickly thereafter. The other study predicts that parts of Europe, Asia, North Africa and Canada could see a rise beyond two degrees Celsius within just twenty years.

Running out of time

How do we stay below a global rise of two degrees Celsius? According to a new study involving researchers various climate institutes, greenhouse gas emissions would need to peak during the decade and fall to 44 gigatons by 2020. Emissions this year are expected to hit 48 gigatons. Dropping 4 gigatons may appear easier than it is as experts consider many future emissions to already be 'locked in' due to fossil fuel power plants that are already running or currently under construction. In this case, some power plants would have to be abandoned altogether to keep the world under two degrees Celsius. However, even this scenario provides only a 'likely' avoidance of keeping warming below two degrees Celsius. For a much more certain effort (90 percent chance) emissions would need to peak during the decade but fall even more quickly. In addition, negative emissions, i.e. sequestering carbon from the atmosphere, would be required.

Castle Gate coal-fired power plant in Utah. Nearly half of the US's electricity is from coal, the most carbon intensive energy. Photo by: David Jolley.

Given these findings international agreements and national pledges made to date will not keep the world below two degrees Celsius warming.

"There are significant risks that the [two degrees Celsius] target, endorsed by so many nations, is already slipping out of reach," write the authors.

Still, a number of poorer and climate-vulnerable nations are pushing for halting global warming at 1.5 degrees Celsius, a target viewed as safer for many parts of the world. The recent study found that none of the 139 models they surveyed, no matter how aggressive at cutting emissions, limited warming to 1.5 degrees Celsius.

"However," write the authors, "some scenarios in our set bring warming back below 1.5 Celsius by 2100: a first scenario does so with a probability of about 50 percent, and a second scenario with a 'likely' chance (better than 66 percent)."

In our lifetimes

Contrary to the perception that climate impacts are far in the future, new research and evidence shows that climate change is at our doorstep—if not already inside the house. The other study from Nature finds evidence that if greenhouse gas emissions remain high, the Earth will cross the two degree Celsius threshold by 2060. Even then many regions are set to pass the target much sooner as warming is not uniform throughout the world; in general the northern hemisphere warms quicker than the south.

"Large parts of Eurasia, North Africa and Canada could potentially experience individual five-year average temperatures that exceed the 2 degree Celsius threshold by 2030—a timescale that is not so 'distant'," the authors write.

Such a rise is expected to have impacts on agricultural production, sea levels, biodiversity, extreme weather, public health, food security, and even warfare.

Political mire

Avoiding rising above two degrees Celsius is entirely possible: a recent study in Energy Policy found that fossil fuels could be wholly abandoned by 2050 with the world's energy needs met by electricity produced 90 percent from wind and solar sources alone. The final 10 percent could be generated by geothermal, hydro, wave, and tidal power. Ground transportation would be run by electricity or hydrogen fuel cells, and planes would be powered by liquid hydrogen.

Kentish Flats wind power in the UK. Photo by: Phil Hollman.

However, the effort to push toward such an energy revolution has been stymied for decades by a lack of political will and finger pointing. The US, the world's historically largest emitter of climate change, blames rising powers like China and India for not doing enough as their emissions are rising the fastest. For their part, China and India blame the US and other wealthy nations for not accepting deeper cuts, since they share the brunt of historic responsibility.

Even after decades of increasingly dire warnings, the US has still not passed comprehensive federal legislation to combat global warming; Canada has abandoned past pledges in order to exploit its emissions-heavy tar sands; China continues to depend on coal for its energy production; Indonesia's effort to stem widespread deforestation is facing stiff resistance from industry; Europe is mulling pulling back on its more ambitious cuts if other nations do not join it; northern nations are scrambling to exploit the melting Arctic for untapped oil and gas reserves; and fossil fuels continue to be subsidized worldwide to the tune of $400 billion. Meanwhile global population continues to soar (set to hit seven billion at the end of this month) and greenhouse gas emissions remain on the rise. The only nation that appears to take climate change truly to heart is the small Pacific island nation of the Maldives, which has pledged to be carbon neutral—eliminating or off-setting all emissions—by 2020. The Maldives is imperiled by rising sea levels that could put parts of the islands underwater for good.

Not everything is gloom-and-doom. Australia is close to enacting its first tax on carbon emissions. California, the world's eighth-largest economy, has approved rules for its cap-and-trade program set to begin in 2013. Investment in clean energy has jumped 670 percent in less than a decade with China well out front and Germany moving aggressively to a renewable-energy society.

The next chance for the international community to come together to address climate arrives in little more than a month at the UN climate talks in Durban, South Africa. However, international chatter ahead of the climate talks have expressed low expectations for any binding agreement.

When will we be able to take really effective action? I fear not for about twenty years. I think after continued warming and some nasty effects denialists will have become a spent force.

But even after the denialists are marginalized (We won't completly get rid of them.) there will be problems about what should be done. The danger then will be panic measures and measures made more to make a staement of concern. These can unnecessarily push up the cost of mittigation. We will need to make careful and realistic calculations of the cost and benefit of mittigation measures. The denialist concern that mittigation measures could provide a means for special interests to rip off the populace is reasonable. I think we just need to be on guard against them. I think self righteousness on the part of climate change activists can make them vulnerable to exploitation by such interests.

What we're now faced with is selecting from the least worst processes and outcomes, rather than the good, the best, the economical, the gradual or the preferable.

The best analogy I can think of at the moment is the River Murray. We knew we were in deep doo-doo the day in 1981 the mouth of the river closed 'despite' all the management of flows and levels. SA irrigators started modernising and restricting their take from the river while those further upstream increased their take and kept on with their lax (or lack of) technology. (It's a good idea to shield your face from the flying spittle when you talk to SA farmers recounting their horror stories of visiting eastern state orchards with their primitive open channels blithely evaporating tonnes of water.)

30 years later? Still arguing. Still proposing that upstream irrigators should be able to take more than scientists say is the absolute maximum they should be allowed if the river is to survive. And they'll still be arguing if they get their way. The next drought reducing the river to a filthy trickle will be described, again, as the fickleness of nature.

A bit of a parallel, within a single country, to the North-South divide we see unfolding with climate impacts largely caused by northern hemisphere countries being felt first and worst by those nearer the equator.

I suspect that the denialist response to being marginalized will be to claim that nobody ever doubted that mankind was responsible for the warming. The contention was always over resolution methods, with geoengineering projects on top of Business As Usual (BAU) trotted out.

The cartoon show Futurama showed that humanity "solved" global warming by dropping mountainous slabs of extraterrestrial ice into the oceans every year, starting in 2063.Youtube: Futurama - None Like It Hot

It's policy as described by nursery rhymes.

I know an old lady who swallowed a spider,
That wriggled and jiggled and tickled inside her.
She swallowed the spider to catch the fly,
I don't know why she swallowed the fly,
I guess she'll die.

So Camburn, are you trying to say that you dont think there will be any more El Nino's and so we dont need to worry about global warming any more? It looks to me like only a moderate El Nino will enough to break all surface and satellite temperature records.

If you dont like the current administration do you think an alternative are going to get real about climate? (isnt Perry leading runner?).

scaddenp:
I am sure there will be more El Nino's, but not in 2012 as the prediction is for a moderate to strong La Nina.

There are so many things wrong with the current administration it is hard to start. Perry is at the bottom of the pack as far as Republicans. The flavor of the week is Cain, but he is getting out of flavor now. As far as climate, the US has been cooling so that is a hard sell. And the current economic climate because of the spending and increased debt of the Feds is so bad that people are concerned how they are going to eat tomorrow and not worried about next week.

00

Response:

[DB] "As far as climate, the US has been cooling so that is a hard sell."

Straw man. You say climate but mean weather/season. It is November in the USA so the temperatures do their seasonal trend downwards. Seasonal cycle superimposed on the long-term rise in global (not just the US) temperatures.

As far as an El Nino breaking temp records, it would have to be one heck of a El Nino.

As far as AGW, I have never been to concerned about that. I am concerned about the lowering PH of the oceans tho. We have had periods within the Holocene as warm as the projections from the models and survived quit well. In fact, one period was called the Holocene Optimum.

But we have NOT had periods of warmth and the lowering of the PH of the oceans within the Holocene. The extra co2 benifits plant growth, but is very detrimental to the oceans. I do not think the carrying capacity of the planet can continue if the effects on sea life is as currently presented as the oceans are still a major source of food.

In short, utterly short-sighted, narrow-as-your-nose thinking from nation that you look for leadership from. I dont think you have a hope of predicting whether there will be El Nino or not in 2012 but I find it depressing that you have to hope for one to get any kind of action. When you can only get action during an upswing it makes you lament. "Oh its, warming" - no, change policy, its cooling, - no wait its warming again". This is mind-boggling unreasonable - send everyone back to school.

Sphaerica:
This is the opinion of over 50% of my countrymen/women as it pertains to the USA. The last poll had jobs as number one, climate didn't even score in the top 20.
I am expressing what the majority of Americans feel at this time. Concerning the current administration, the last poll had it at 32% approval of economic policy.

#12: "As far as an El Nino breaking temp records, it would have to be one heck of a El Nino." 2010 was hottest/tied hottest/damn close to hottest (depending on temperature record) with a moderate El Nino, during the deepest solar minimum in nearly a century. In the intervening years, solar forcing has at last risen on the way to a peak in the next few years and CO2 forcing continues to rise. It's going to take one heck of a small El Nino to break the temperature record. There, fixed it for you. Equatorial volcanic paroxysms aside, we'll be seeing new temperature records quite soon enough.

As for the US versus the world, I can only shake my head in amazement that you are unable to look beyond your own borders. The effects of warming are being felt all over the US through some remarkable weather extremes, be they snowstorms driven by high precipitation, large floods or desperate droughts. Around the world, news events that are part of the growing story abound, Thailand, Italy and Central America being the latest extreme flooding victims. Clearly you'd like those to continue because in your opinion, it's cooling in the US?

We can be sure that US daily record high temperatures will continue to far outstrip US daily record lows (cooling? sure...), and also equally sure that US Republicans will ignore the problem until it's pretty much too late to straightforwardly solve it.

Camburn - sadly for humans on this planet - it doesn't matter what an opinion poll says: objective reality exists. And the scientific method is our best window on that objective reality. And of course that process tells us the world is warming, and that man is to blame.

Now, while you are right to be concerned about the ocean ecosystem - it is going to collapse with or without the change in pH (yes there are other problems besides global warming - try over-fishing as just one).

But oceans provide 5% of the global food supply. You should worry more about the flooding in the rice belt.

Climate change will show no mercy - all our systems are adapted to the current climate, and the new regime will be much less forgiving, much less productive and much more volatile.

Earth's carrying capacity for humans is probably well below 7 billion with currently deployed technology. I believe we are in an overshoot right now, with global warming being only one of the ways the interconnected systems of the earth are automatically acting to reduce the human population.

Not happy about any of that, but I think it is important to focus on the core problem from time to time.

The big problem with Americans is that the MSM has failed. They ignore climate change, for the most part, unless it's something juicy that will help their ratings.

Basically, the U.S. media has gone two routes. Most of them are commercial enterprises focused on making a buck (or just plain staying afloat). As such, there is no responsible reporting or selection of material. Everything is sensationalism. Respectable journalism is dead.

The flip side is Faux News, which both is out to make a buck from their chosen shills (the fiercely and ignorantly right wing middle class and lower middle class) as well as to push a particular agenda, i.e. right wing "values."

This means that they attack and misreport climate change religiously.

The end result is that Americans are more concerned about other topics. There is concern about climate change, but not immediate concern.

And I question Camburn's 50% number until he demonstrates some proof. I've seen the numbers on climate change dropping, but nothing like 50% thinking negatively about climate change (although I note that Camburn did not clarify what that 50% actually think).

Separately... I don't know if anyone is actually measuring things from year to year, but... it is now November 6 and a lot of trees here (Massachusetts) are still green. By now more than half shouldn't even have any leaves, and they should almost all have turned.

The trees did start turning yesterday and today, but they are skipping the yellows and reds and instead going straight to green-brown.

Too bad about the La Nina vs. El Nino. An El Nino in an election year would put the issue front and center.

I believe we will see record temperatures, even with a La Nina. But the El Ninos in the US tend to put impressive weather on display.

I for one would love to see the Republicans argue that global warming is not happening as they campaign (spin) during the extremes of an El Nino summer. That would put the issue front and center, and force Republicans to address the issue.

skywatcher@17:
I have posted links to NOAA Climate Slueths on this site. The weather in the US is not the result of AGW. At least that is what the experts tell us.
Documentation that the highs are outnumbering the lows in the USA please? With statistical signifance as well.
Thank you.

actually thoughtful@18:
Being we can discuss politics, and I am from the USA, real clear politics has ongoing polling data. It is what it is.

I think the USA is in exaustion mode and I don't like that. Our debt is rising so fast that it is akin to Greece. The trajectory of the graph of debt to GDP is not substainable. People recognize this economic reality and it creates uncertainty. When you add one more uncertainty, climate, to the multitude that are presently here, and it is a future uncertainty, people will put that on the back burner. Yahoo news had a blurb about the protests in Washington today. Read the comments, they are informative of the mood.

Yes, over-fishing is just one problem of the ocean. But the fast change in PH is an immediate problem and the science is very cut and dried with high certainty. That makes it an easy sell to most people.

Sphaerica - I grant you the point that the trees are turning later (much later). But the skipping the yellows and reds bits, as I recall, is due to how quickly the frosts come, the amount of sugar in the tree and other not-directly-climate-change issues.

Have you considered that both climate change and increasing competition for dwindling fossil fuel resources is putting the U.S. on a collision course with complete melt down? That the economic and military and moral standing of the U.S.A. is at stake, simply for the sake of short-sighted, selfish thinking?

Why in the world wouldn't and shouldn't the U.S.A. wean itself from dependence on fossil fuels, and so secure its own long term independence and prosperity?

As far as fossil fuels, the USA has so many fossil fuel sources that have not been developed that this is really not an issue. The Rocky Mountain shale has approx 2 trillion barrels of oil, the Bakken has 25 billion barrels, and the Canadians have approx 2 trillion barrels in just the tar sands.

As far as military, the spending for the offensive military of the USA is complety utterly nuts. President Eisenhower warned us about the military industrial complex, but most people are too young to remember, nor heed his warning.

As far as moral standing, instead of having folks such as Solyandra in the news, I would much prefer having thorium salts in the news. That we have developed a reactor that is safe, efficient, and best of all, no co2 or very little co2 emmitted. This has been an integral part of my solutions for years, but I get a lot of resitance which I have never understood.

The USA is close to a meltdown right now. In fact, the world as a whole is close to a meltdown. The sad fact is, when the economics of the world is precarious, the development of new technologies does not proceed at a pace that is condusive to well being.

My understanding of the biology is that the color change comes when the trees stop producing chlorophyll, which gives leaves their green color. The remaining pigments as the chlorophyll vanishes are what give them their color, although they've always been there.

The leaves fall, on the other hand, when the veins close up and trap the sugars in the leaves and promote the production of anthocyanins.

Scientists do not entirely understand what triggers these changes, but certainly temperature and length of day are two factors.

Taking a systemic point of view, it behooves the tree to keep producing chlorophyll for as long as it is effectively "feeding" the plant. If temperatures drop or days get too short, it's not worth the effort anymore.

My supposition is that the warmer weather could be leading trees to be able to hang onto their chlorophyll longer, but it's a losing battle because even if the temperatures stay warm, the days start to get too short.

At the same time, there are other reasons for losing their leaves, as we in the Northeast have just seen. The early, heavy, wet snow at the end of October has caused a huge number of power outages, because snow usually falls after the leaves are off of the trees. The branches are not strong or pliable enough to hold the weight of the snow that can be supported by a canopy of leaves. The result is a lot of broken branches and felled trees, which in turn fall across roads and onto power lines.

So the period during which the chlorophyll has dried up but the leaves are still on the trees is shortened (i.e shorter periods of fall colors) while the leaves are staying on the trees longer. Finally, the chlorophyll starts to dry up and the leaves start their shut down process soon after.

I'm not a plant biologist. This is my understanding and supposition only. But one way or the other, this fall is unusually warm in the Northeast, and the trees seem to be responding to that in a very, very unusual way.

Your need to tie short-sighted economic fear to a need to continue BAU (or, worse, start frantically trying to tap shale deposits) points to a major disconnect in your thinking.

There is no reason why transitions to other energy sources could not only be done smoothly and efficiently, but economically. There's no reason why it shouldn't cost less to switch energy sources rather than more.

Camburn, you write of oceanic pH:
"the science is very cut and dried with high certainty."

This is also true of climate change (it is the same CO2 - from man's actions - that is to blame in both cases).

The science is settled and the solutions are obvious. The latest research shows that renewable energy systems grow the economy (beyond the research documented at this site, look at Germany and China - the two world leaders in renewable energy).

adelady:
The current drought in the USA in the southwest, south central is pretty normal.
The drought of the 1950's in that area was more severe than the current drought.
The La Nina has stengthened the drought this year, and there is worry that this will turn into a two year drought because of NOAA's forcast of another La Nina.

Camburn - The graph, and the paper involved, is Meehl 2009, as described in the link (which I'll note should be clear if you read it). The period of that study is 1950 onwards.

I will point out that it clearly demonstrates that record highs exceed record lows over the last 35 years. Before that, in the 1940's to mid 1970's, during a cooling phase, lows exceeded highs - as expected. Looking at the historic records, I would also expect highs to also exceed lows from 1910 to 1940, with more variation before that.

I answered your question - "Documentation that the highs are outnumbering the lows in the USA please?". You then moved the goalposts. That's quite disappointing, Camburn, trying to change the question. But your original question is well answered, and your assertion contradicted, by the data I pointed to.

Spaerica:
I posted what is known as far as energy reserves of oil. I won't even get into the coal, lets say of just the Powder River Basin.

I have no fear about renewables. I know their costs as our elec co-op owns part of a windfarm. Even with the subsidies, the cost of wind in a class 5 wind area, and I have a windfarm approx 14 miles west of me, is approx 2.3 times the cost of our coal supplied generating stations.

Speaking from my operation, if you raise the cost of energy even more, it will only cause more contraction of food output and higher prices. This ripples throughout the economy. There are only so many dollars to go around.

On opinion polls, Camburn, you might be interested in this recent one, run by Republican firn Public Opinion Strategies. "Fully 71 percent indicate support for requiring reductions in carbon emissions, including a solid majority of Republican voters." [Sept 22nd]

This Reuters poll shows "The percentage of Americans who believe the Earth has been warming rose to 83 percent from 75 percent last year in the poll conducted Sept 8-12." "Global warming could be an important issue in next year's election, because some 15 percent of voters see it as their primary concern". Camburn, do you have polls that support your point, because these ones from September completely contradict you.

Source for record highs outpacing record lows in the US. At NCDC you can see the current pace of record highs vs record lows is 2:1 for the past year (as it was over the past decade too), reaching 5:1 in July.

adelady - I don't actually now how to answer your question. I can assure you that Australian issues with climate change do not motivate the rank and file American (and I think it should -but for the Grace of God...).

Texas, with a climate change denying Presidential candidate as governor, provides a delicious (although deeply tragic) marker for what climate change means for the US.

My sense is that Americans think most about climate change during 1) hot summers and 2) dramatic weather events.

Droughts don't seem to count. Floods are good. Tornadoes seem to alert people. Most Americans can't seem to reconcile "global warming" with anomalous cold weather. It seems to blow a fuse in the typical American's logic board, and they either ignore it or ridicule the notion of climate change bringing more snow, harsher winter storms. I think they are looking for the 20-50 year effects, when winter storms will be more energetic, but wetter/warmer.

I am in a strange place, that our President calls an "Eat your peas" moment - I think we need some significant bad news on the catastrophic storm front to move this country to a position where the world (including the US) suffers fewer catastrophic storms over the long term.

I also cheer energy price increases, as even the uninformed free market is shouting that "cheap" fossil fuel is a myth. I would much prefer if we sent the extra money from high fuel costs to Americans (through a tax) to research and create a carbon free economy, rather than sending the money to terrorists in the Middle East so they can buy weapons to attack my country.

But this logic is lost on my fellow countrymen who prefer denying the whole thing exists because it is more complicated than "when you are spending more than you bring in you STOP spending" - which seems to be the amount of mental effort people in this country are willing to dedicate to the tough problems we face as a nation.

While Camburn's numbers regarding support for climate change policy are completely bogus - your question might be better directed at him as he seems to understand the whole "do nothing" agenda, which I find inexplicable.

Your continuing insistence that early 20th century warming was equivalent to current warming is not supported by the data - and I would personally consider it continued denial. The forcings were different, the temperature didn't go anywhere near as high, and the current rise in temperatures is going to continue due to the physics involved. As someone said recently, physics has more predictive power than statistics, which have more predictive power than statistics done badly.

"This drought has been the most intense one-year drought in Texas since at least 1895 when statewide weather records begin, and though it is difficult to compare droughts of different durations, it probably already ranks among the five worst droughts overall. The statewide drought index value has surpassed all previous values, and it has been at least forty years since anything close to the severity of the present drought has been experienced across Texas."

KR:
The rate of rise in the early 20th century is statistcally identical to the rate of rise from 1970-2005.
As far as the actual temperature, yes, it is warmer worldwide now than in the early 20th century. I expect that, and if it wasn't I would be really worried. We just exited a Grand Maximum. One expects temperature rise during and after a Grand Maximum because of climate inertia. If you want to comment more on this topic I will certainly respond, but not tonight, in the What caused 20th century warming topic.

skywatcher:
Note I mentioned the drought of the 1950's. Note the 40 years in your post.
Texas has droughts each and every decade. That is their climate. This drought is severe, and will prob continue as a result of the upcoming La Nina. If it does, it has the potential to exceed the 1950's drought.

By all means Camburn, look at your link. Look at when the call for action spiked. It was exactly during/after the last strong El Nino (98/99). Which is my point from awhile ago. And the rest of the link supports that your 50% number is bogus. Try reading what you link to.

This statement is completely false:"There are only so many dollars to go around." - Camburn

The whole point is that renewable energy creates jobs, and jobs create money, and that new, never seen before money expands the economy which creates jobs. Lather, rinse repeat.

If it really were a non-expanding pie, then each generation would have to split the exact same amount of money with more and more people, and the standard of living over the last century would have declined.

Other than a few periods under right wing leadership in the US, the opposite has been true.

#46: Which post? The one where the Texas state climatologist is quoted as saying 2011 was the most severe one-year drought since at least 1895? Or was it John N-G's post spotting the outlier, in data since 1895? You suggested in #34 the drought is 'pretty normal', yet it is the most extreme single year of drought on record.

Your #47 seems irrelevant, yes, Texas has droughts (surprise!), but 2011 was extreme. It should be a wake-up call to certain Republican candidates, but they prefer to pray for rain...

skywatcher:
So we have a repeat of extreme droughts, of which Texas has had many as documented in the historical link...and you are trying to say this particular drought is all of a sudden the result of AGW?